Conventionally, in order to measure a gas dissolved in oil, the following methods have been used.
In a first method, an oil sample is taken at a site, placed in a closed vessel and taken to an analysis room where an analyzing apparatus is provided. In the analysis room, a sample of oil from the vessel is put into an analyzer which extracts dissolved gas from the oil sample, and analyzes the extracted gas using a gas chromatograph to measure the kind and quantity of the dissolved gas.
In a second method, a permeable membrane flange is connected to an oil take-out valve on oil handling equipment, and a gas chamber is provided on the outside of the permeable membrane flange so that gas in oil passing through the permeable membrane is detected and the kind and quantity of the dissolved gas in the oil is measured.
In the first conventional method, there has been a problem in that it takes a long time from collecting the oil to analysis, so that the measurement of the gas is delayed, and the gas sometimes comes out of solution during transportation, thereby lowering the reliability of data. Further, the analyzing apparatus is expensive, and the analyzing operation is complicated and requires a skilled operator.
In the second method, on the other hand, there has been a problem in that the gas transmission time is three days or more, so that rapid evaluation cannot be performed. Also, it is necessary to provide a permeable membrane flange and a gas chamber for the oil handling equipment, so that the manufacturing cost of the equipment becomes high.
It is therefore an object of the present invention to provide a method and apparatus for measuring dissolved gas in oil with a simple arrangement in a short time.